The current Japanese reactor fleet includes only two units generating power at present (Ohi-3 and -4). JNES had left only one additional reactor in the “In operation” category, Tomari-3 in Hokkaido. Tomari-3 is the last unit to have been taken off the grid for “periodic inspection” on 5 May 2012, before the country entered a two month nuclear-free period. In July 2012, the two Ohi units were reconnected to the grid. As of today, all but two of the 47 units that JNES correctly had moved to LTS have been shut down for over one year. The remaining two units, Takahama-3 and Kashiwazaki-kariwa-6 were taken off the grid on 2 February and 26 March 2012 respectively. In other words, even these two reactors had been shut down for over eleven and close to ten months respectively. Thus, the first criteria of the IAEA’s LTS definition is clearly fulfilled, as all of the units have been shut down “for an extended period (usually more than one year)”. The average shutdown period of the 47 units is almost two years (23 months)—average exceeds two years, if one adds the Monju reactor—with a maximum of 5.5 years for three reactors at the Kashiwazaki-kariwa plant that have been down since an earthquake in July 2007.

According to the IAEA definition, one of two additional conditions should be met for the LTS category, either that “restart is not being aggressively pursued” or “no firm restart date or recovery schedule has been established but there is the intention to re-start the unit eventually”. In fact, both of the conditions are met by all of the reactors. The classification obviously does not judge whether re-start is a realistic option. The World Nuclear Industry Status Report does not consider plausible the restart of any of the remaining six Fukushima reactors (Daiichi-5 and -6, Daini-1-4) and has taken them off the list of operating reactors. Nevertheless, at the very least, these units should be in the LTS not in the “In operation” category.

The analysis of the historic use of the LTS category (see Table-2) shows 13 units that have been listed there in the past. Only one is still on the list, the Japanese fast breeder reactor Monju that was shut down after a sodium fire on 8 December 1995. Two Canadian reactors were moved from LTS to “Permanent shutdown” and 10 units restarted after an average shutdown period of over 10 years, with a minimum of five and a half and a maximum of 22 years.

The agitation around the reclassification of the 47 Japanese units appears to be a political attempt to undermine JNES’ attempt to bring the official status of the nuclear plants in line with reality. The reactor status incident could well turn into a political affair in the near future.

What They Say…

“The Report sets forth in painstaking detail the actual experience and achievements of nuclear energy around the world.”

Peter A. Bradford

Former commissionerU.S. Nuclear Regulatory Commission (NRC)(in his foreword to the 2013 report)